From the moment you approach the building, the Semiramis hotel embraces you in true Miami style. From the citric yellow glass balconies glittering across its white facade to the light-filled lobby decorated by lounging couples and chic women sipping coffee to the shiny happy staff, it's a cotton-candy coloured destination that overwhelms the visitor with feelgood factor 25.

There's just one problem. The Semiramis is not in South Beach but Kefalari. And no, you won't have heard of it. Kefalari is Athens' poshest northern suburb, an area of neo-classical villas and tree-shaded streets where women in (real) Chanel tweed jackets walk small dogs and beautiful young people with perfectly modified noses and the very latest mobile phones languish on the street corners. Imagine if Ian Schrager brought his latest Philippe Starck-designed hotel to Hampstead, or Wilmslow, and you're half way there.

The Semiramis has nothing to do with Schrager, though it owes not a little to the Schrager/Starck heritage in terms of design, and to the Hotel W chain when it comes to service. While the latter's motto is Whatever Whenever Wherever, the Semiramis is the first in a chain of Yes Hotels. "That's the answer we'll always try to give our customers," says a representative.

The hotel's designer, New York-based Karim Rashid, has a zest for self-promotion that makes Victoria Beckham's approach to the business of being out there look lazy and unstructured. He is tall and gangly and has dressed head to toe in white since the year 2000 when he gave away all his black clothes to charity. His willowy girlfriend, the artist Megan Lane, has adopted the same palette, and together they can be said quite literally to swan into a room.

Rashid was the choice of the hotel's owner, Dakis Joannou, who is an important though remote Athenian figure. Joannou, a rich industrialist, is a serious art collector and the man behind the Deste Foundation, a major private gallery in Athens. His collection of contemporary art is among the best. He has the largest collection of Jeff Koons, and some of the most desirable Chris Ofili's and he is allowing a number of works to be hung in the hotel on a six-month rotation. Currently you can sit beneath a vast Jeff Koons photograph in the bar, and admire an abstract by Christopher Wool while you wait for the lift. The first selection is based on people and sex. The next will be about service and cleaning, and include the famous Jeff Koons vacuum cleaner, taking pride of place in the lobby. "That's what people think of first with hotels. Sex and cleaning," says Rashid.

You wonder if Naomi Campbell appreciated the proximity of the art when she arrived at the hotel on August 12 this year, two days after its opening. To the understandable consternation of hotel staff, Campbell was to be the first guest in the best suite. By all accounts she was no trouble, her special requirements including a fruit platter with bananas, a lot of ironing, and the slightly unusual need for access to secretarial services at three in the morning. Perhaps she, too, was charmed into sweetness by the hotel's twinkly design. Artists Tim Noble and Sue Webster, whose work figures large in Joannou's collection and in the hotel lobby in the form of a huge, flashing YES, also came to stay for several days during the summer. Rashid says they never left the hotel. It is that kind of place, out of context in its leafy suburb maybe, yet utterly seductive in itself.

The hotel Rashid inherited was a standard early 20th-century building that had seen its share of glamour in the 40s and 50s when this part of Athens was still an outlying suburb favoured by the rich in the summer months. (It's a good 12km from the centre, but only 15-20 minutes by metro.) He wasn't able to change the number or size of the rooms, though he has changed just about everything else. The ground floor is glazed, front and back, in fruitily coloured glass, making it completely seethrough. Internal spaces are generous, and with as many internal walls as possible also being glass, you get long layered views. The Athenians are obviously taken with this permeable internal architecture - on Friday and Saturday nights you won't get a restaurant or bar table without booking, queueing or knowing the right people.

At the back is a sensational swimming pool which is pure 50s Americana in its slinky shape and stripy tiled bottom. By night, as one of my party pointed out, it looks like the polar bear pool at London Zoo.

Up in the rooms, the candy colours prevail; apricot and primrose carpeting, acid green and raspberry glass, banana yellow rubber flooring in the bathroom. There are palest pink leather armchairs and Rashid's own translucent plastic artefacts everywhere.

The only dent to the feelgood factor comes at night. Those brilliant yellow balconies are illuminated throughout the night, and if you are staying at the front of the hotel it's like having a car parked outside your room with full beam on. For once the reception staff had to say "no" when asked if it was possible to turn them off. They said it so apologetically, it clearly wasn't the first time.

Rashid believes in a seamless, person-oriented hotel experience, and he has got many things right. He wants it to be about the total experience, rather than individual elements, and indeed it does all wash over you in a delightful wave of colour turned up to volume 11.

"I was working on a hotel in Miami that never got built when I got the call," he says, talking about the day Joannou gave him the job in 2001. He's now working on a myhotel for both Brighton and Paddington. Will we get Miami, or maybe this time it will be Athens?

Where to eat: At Gefseis Me Onomasia Proelefsis (Leof Kifisias 317, +210 800 1402) every ingredient is sourced from regional farmers, and then treated to exquisite preparation. The restaurant itself is in a perfectly restored mansion with garden to match. Vegge (Koloktroni 9, +210 808 0009) is the city's only decent vegetarian restaurant, with a lovely veranda, too. The food is good, though hardly radical. Ya hala (Kolokotroni 37, +210 801 5324) is surprisingly cheap for Kefalari where restaurants err on the pricey side. The food is Lebanese and the atmosphere easy going, right down to the after-dinner hookah smoking.